Heretofore, coffee roasting was effected merely by passing heated combustion gases or air over the green coffee beans positioned in a rotating roasting drum or oven, wherein the heated gases passing through the roasting oven was exhausted to atmosphere together with coffee bean shells or chaff and/or other coffee residue. Such apparatus and methods released harmful impurities and odors into the atmosphere. Accordingly, many regulations have been put in effect in an effort to control or limit the amount of odors and impurities that coffee roasters are permitted to exhaust to atmosphere. As a result, the conventionally known methods and/or apparatuses in many instances cannot meet some of the more rigid standards currently being put into effect.